At present, the distribution of compressed air in industrial premises is somewhat akin to plumbing in the sense that it is essentially made-to-measure, with pieces of tube being cut to the required length on site for fitting to the geometry of the premises, and with the lengths being connected to one another in order to build up a continuous main pipe that goes past workstations or groups of workstations requiring compressed air, with tapping points being provided on said main pipe from which the compressed fluid is taken to points of use. In general, such a main distribution line is located high up in industrial premises and secondary lines constitute vertical down pipes running from said high pipe, or else they constitute secondary horizontal pipes from which further vertical ramifications can be extended.
In general, branch lines are connected to the main line via swannecks, particularly when the network distributes compressed air, since the bottom portion of the main line collects condensation water and it is desirable to avoid entraining said water towards machines that use the compressed air.